The present invention relates to a heat dissipation device, and more particularly, to a heat dissipation device having bidirectional air channels.
With highly development of information technology, operating rate of electronic components in a computer (e.g. a CPU) has been greatly improved, and use of computers are becoming easier and easier.
However, high operating rate electronic components produce too much heat during working, if the heat generated is not removed immediately, a performance of the electronic components will be reduced and the electronic components will even be burn out.
Typically, a generally used heat dissipation device includes a heat dissipation member and a fan secured above or at a side of the heat dissipation member. The heat dissipation member is usually made using an aluminum extrusion process and includes a base, a number of spaced arranged heat dissipation fins extruding from the base. The heat dissipation fins define heat dissipation channels therebetween. A bottom surface of the base is attached to a heat-generating electronic member.
The heat generated by the electronic member is conducted to the base and finally dissipated to the ambient air by blowing air to the heat dissipation fins using the fan.
In such instance, the electronic member is covered by the base of the heat dissipation device; therefore, the air blown by the fan can't come in direct contact with the electronic member whether the fan is above or at a side of the heat dissipation member. The heat generated by the electronic member is transferred only through a heat conduction process, which is insufficient in many circumstances.
Therefore, another type of heat dissipation device is developed to overcome above problems, which includes a fan, a heat dissipation member, a heat spreader and a number of heat pipes. The fan is secured above the heat dissipation member. The heat dissipation member includes a number of through hole therein, and the heat spreader includes a number of through grooves defined therein. The heat spreader is attached to a heat generating electronic member. The heat pipes are received in the through holes and the through grooves.
Compared with above heat dissipation device, heat dissipation efficiency is greatly improved as the working fluid contained in the heat pipes can absorb a lot of heat when the working fluid is gasified. However, if a bottom portion of the heat dissipation member is closed, the heat is also transferred to the heat spreader through heat conduction; if the bottom portion of the heat dissipation member is open, the air blown by the fan dispersed immediately.
Therefore, there is a desire to develop a heat dissipation device which can overcome above disadvantages and achieves maximum heat dissipation efficiency.